Add XapiDb

bin/main.ml

@@ -16,9 +16,13 @@ let () =
     Printf.eprintf "You must specify a log file using -log\n";
     exit 1);
 
+  if !dbfile = "" then (
+    Printf.eprintf "You must specify a db file using -db\n";
+    exit 1);
+
   let open Inspector in
-  let s = State.create !logfile in
-  Printf.printf "dbfile is currently ignored\n";
-  Printf.printf "Loaded %d lines\n" (State.size s);
+  let s = State.create ~logfile:!logfile ~dbfile:!dbfile in
+  Printf.printf "Loaded %d lines from logs\n" (State.size s);
+  Printf.printf "Found %d entries in the DB\n" (State.dbsize s) ;
   Repl.help ();
   Repl.loop s

lib/dune

@@ -1,2 +1,3 @@
 (library
- (name inspector))
+ (name inspector)
+ (libraries xmlm))

lib/state.ml

@@ -1,14 +1,16 @@
-type t = { lines : string array; cursor : int }
+type t = { lines : string array; cursor : int; db : Xapidb.t }
 (** Invariant: cursor >= 0 cursor < Array.length lines *)
 
 let size s = Array.length s.lines
+let dbsize s = Xapidb.size s.db
 let cursor s = s.cursor
 
-let create (fname : string) : t =
+let create ~(logfile : string) ~(dbfile : string) : t =
   let lines =
-    In_channel.with_open_text fname In_channel.input_lines |> Array.of_list
+    In_channel.with_open_text logfile In_channel.input_lines |> Array.of_list
   in
-  { lines; cursor = 0 }
+  let db = In_channel.with_open_text dbfile Xapidb.from_channel in
+  { lines; cursor = 0; db }
 
 let show_line s : string = s.lines.(s.cursor)
 

lib/state.mli

@@ -4,7 +4,7 @@ type t
     A [t] represents a loaded log file and a cursor pointing to the currently
     active line. *)
 
-val create : string -> t
+val create : logfile:string -> dbfile:string -> t
 (** [create file] loads the log file into memory and initializes the cursor at
     the first line. *)
 
@@ -22,3 +22,6 @@ val cursor : t -> int
 
 val size : t -> int
 (** Number of lines in the log. *)
+
+val dbsize : t -> int
+(** Number of entries in the db. *)

lib/xapidb.ml

@@ -0,0 +1,130 @@
+type value = String of string | Ref of string (* OpaqueRef UUID only *)
+type e = string * value
+type t = (string, e list) Hashtbl.t
+
+(* ---------------
+        Helpers
+     -------------- *)
+let parse_value s =
+  match String.split_on_char ':' s with
+  | [ "OpaqueRef"; uuid ] -> Ref uuid
+  | _ -> String s
+
+let table_name (attr : Xmlm.attribute list) : string =
+  if List.length attr <> 1 then (
+    Printf.eprintf "For table only one attribute name is expected, got %d\n"
+      (List.length attr);
+    exit 1);
+  let (_, local), table_name = List.hd attr in
+  assert (local = "name");
+  table_name
+
+(** [row_elements attr] return a list of tuple where the first element will be
+    the key and the second element is a value. Example:
+    - host="OpaqueRef:3e.." -> ("host", Ref("3e.."))
+    - type="host_internal" -> ("type", String("host_internal")) *)
+let row_elements (attr : Xmlm.attribute list) : e list =
+  let rec loop acc = function
+    | [] -> acc
+    | x :: xs ->
+        let (_uri, local), name = x in
+        loop ((local, parse_value name) :: acc) xs
+  in
+  loop [] attr
+
+(** [peek_ref elements] return the string that corresponds to "ref" or "_ref".
+    It is the OpaqueRef of the object (element) itself. It raises an expection
+    if ref is not found. *)
+let peek_ref (elements : e list) : string =
+  let _, opaqueref =
+    List.find (fun (s, _) -> s = "ref" || s == "_ref") elements
+  in
+  match opaqueref with
+  | Ref uuid -> uuid
+  | String s -> failwith (Printf.sprintf "OpaqueRef is expected, got %s" s)
+
+(* ---------------
+        Interface 
+     -------------- *)
+let size = Hashtbl.length
+
+(*List.iter (fun e -> Printf.printf "  %-20s\t%s\n" k (XapiDb.elt_to_string v) l))*)
+let elt_to_string elt =
+  let s1, s2 =
+    match elt with s1, String s2 -> (s1, s2) | s1, Ref uuid -> (s1, uuid)
+  in
+  Printf.sprintf "%-20s\t%s" s1 s2
+
+let get_ref t ~ref =
+  match Hashtbl.find_opt t ref with None -> [] | Some l -> l
+
+let from_channel ic =
+  let htable : (string, e list) Hashtbl.t = Hashtbl.create 128 in
+  let input = Xmlm.make_input (`Channel ic) in
+  (* The goal of the loop is to fill the Hashtbl where the key is the OpaqueRef
+       of an element. An element is basically the row but we will see as we go. *)
+  let rec read_loop (stack : string list) =
+    try
+      (* input as a side effect *)
+      let new_stack =
+        match Xmlm.input input with
+        | `Dtd _ -> stack (* can be safely ignored *)
+        | `El_start (tag_name, tag_attr_lst) -> (
+            let _, local = tag_name in
+            match local with
+            | "database" | "manifest" | "pair" -> stack (* can be skipped *)
+            | "table" ->
+                let tname = table_name tag_attr_lst in
+                tname :: stack
+            | "row" ->
+                (* Row is always part of a table and we are not expecting nested table *)
+                assert (List.length stack = 1);
+                let tbname = List.hd stack in
+                let elements = row_elements tag_attr_lst in
+                let ref = peek_ref elements in
+
+                (* We can now insert the element, we should not have duplicated ref *)
+                let () =
+                  match Hashtbl.find_opt htable ref with
+                  | None ->
+                      Hashtbl.add htable ref
+                        (("table", String tbname) :: elements)
+                  | Some _ -> Printf.eprintf "Ref %s is duplicated" ref
+                in
+                (* We need to add the row because when reaching `El_end we will remove
+                     it, and we will have the table on top. It works because we don't have
+                     nested element. *)
+                local :: stack
+            | _ -> failwith (Printf.sprintf "%s is not handled" local))
+        | `El_end -> if List.is_empty stack then stack else List.tl stack
+        | `Data _ ->
+            (* Printf.printf "Data found\n" ;*)
+            stack
+      in
+      read_loop new_stack
+    with Xmlm.Error ((line, col), err) ->
+      if not (Xmlm.eoi input) then (
+        Printf.eprintf "[%d, %d]: Got exception: %s" line col
+          (Xmlm.error_message err);
+        exit 1)
+  in
+  read_loop [];
+  htable
+
+let _sample_xml : string =
+  {|
+<?xml version="1.0" encoding="UTF-8"?>
+<database>
+  <manifest><pair key="schema_major_vsn" value="5"/><pair key="schema_minor_vsn" value="792"/><pair key="generation_count" value="72945"/></manifest>
+  <table name="Certificate">
+    <row ref="OpaqueRef:2b3b5149-e164-25b8-3e5c-b3da1765d060"  host="OpaqueRef:3ec68fc0-3c60-ffa4-e499-6142c369ea39" name="" type="host" uuid="7e514750-435c-c6e8-0272-042f644260f2"/>
+    <row ref="OpaqueRef:082d1948-c3f7-91ae-8793-568c9e888810"  host="OpaqueRef:3ec68fc0-3c60-ffa4-e499-6142c369ea39" name=""  type="host_internal" uuid="bd62e7eb-ab54-82df-9c76-bea4981bf48d"/>
+  </table>
+  <table name="Cluster"/>
+  <table name="Cluster_host"/>
+  <table name="host">
+    <row ref="OpaqueRef:3ec68fc0-3c60-ffa4-e499-6142c369ea39" CERTIFICATEs="('OpaqueRef:2b3b5149-e164-25b8-3e5c-b3da1765d060'%.'OpaqueRef:082d1948-c3f7-91ae-8793-568c9e888810')" uuid="6ff4b261-3e37-47f8-ace1-53556da6fcf2" />
+   </table>
+  <table name="pool_update"/>
+</database>
+|}

lib/xapidb.mli

@@ -0,0 +1,12 @@
+type e (* an element of the database *)
+type t (* the database *)
+
+val from_channel : in_channel -> t
+(** [from_file ic] reads XML from the input channel and build a relational
+    database *)
+
+val size : t -> int
+(** [size t] returns the number of entries in the database *)
+
+val get_ref : t -> ref:string -> e list
+val elt_to_string : e -> string